Current list of EFnet servers
EFnet Home Page [ext. link]
This is the semi-official EFnet home page, follow the “servers” link. This list shows more information such as how many clients are on each server, contact information for the server’s administrators, the ircd version, etc.
If you have a lot of trouble connecting to many servers, you should check out this troubleshooting guide. In general, most people should be able to find at least several servers that allow them to connect.